The present invention relates to transportation of people, more particularly to methods and devices for transferring people between marine vessels (e.g., ships or boats) and/or other marine structures (e.g., offshore platforms) while at sea.
With the United States Navy's introduction of the Sea Base program and of concepts such as Ship-to-Objective-Maneuver, there is a greater need for personnel to be transferred between marine structures (e.g., marine vessels such as ships) while at sea. Unfortunately, such transfer is often quite difficult to achieve because of high sea states and other environmental constraints and influences. Among the various methodologies proposed to address this problem, many have involved ramps, slides, or ladders. Generally speaking, previous concepts have proven to be less than entirely satisfactory due to the varying relative motion between the marine structures.
Of interest are the following United States patents, each of which is incorporated herein by reference: Greene, Jr. U.S. Pat. No. 6,309,160 B1 issued 30 Oct. 2001 entitled “Offshore Personnel Transfer System”; Bernal U.S. Pat. No. 6,131,224 issued 17 Oct. 2000 entitled “Coupling Device for Transfer between a Static Structure and a Dynamic Structure”; Wehmeyer U.S. Pat. No. 5,203,425 issued 20 Apr. 1993 entitled “Personnel Lift Devices”; Hill U.S. Pat. No. 5,160,286 issued 3 Nov. 1992 entitled “Personnel Transfer System”; Kimon et al. U.S. Pat. No. 4,412,598 issued 1 Nov. 1983 entitled “Personnel Transfer Apparatus and Method.”
Hill U.S. Pat. No. 5,160,286, afore-noted, discloses personnel transfer apparatus that can be used as a buoyant support for persons in water as well as for transferring persons between marine vessels. Hill is largely concerned with floatability of his apparatus. According to his preferred embodiments, Hill provides a buoyant, shock-absorbing base supporting the deck of his cylindrical chamber, and further provides for his chamber plural peripheral posts (usable for lifting purposes) and a central post (not usable for lifting purposes) that can include foam material for enhancing floatability and padding for protecting the occupants. Hill provides embodiments of his apparatus “of the sitting type” (which includes a central bench, or two central benches with a safety belt for each) and “of the standing type.” Among the drawbacks of Hill's apparatus are its rather cumbersome nature, its inability to accommodate large numbers of occupants, and its inability to protect the occupants from shaking, jolting and jostling that may accompany hoisting of his apparatus.